After a week of racing industry speculation and rumour, both men were relieved to finally complete the sale.

Kolivos, the Sydney financier who says he has been "living the dream" racing Pierro with his wife, Donna, and their son, Alex, has retained a small interest in the champion three-year-old.

"We could not let him go," Kolivos said. "We wanted to say involved with the horse in some capacity.

"Until we decided Pierro was retired - and that wasn't done until Gai (Waterhouse) made the call last Sunday - we had not formally commenced any negotiations to sell the horse.

"But once we had made the decision that Pierro had run his last race, we started the process of finding him a new home. Coolmore seemed the perfect fit as they are one of the most successful breeding organisations in the world, they have a fabulous track record, and we can still go and visit the horse at the farm.

"If Pierro stands outside Australia, then if we go on a family trip, we can visit him there, too."

Magnier said details of the Pierro deal are "commercially sensitive" and neither he or Kolivos would comment when asked about the sale price.

However, Magner said the Coolmore organisation, which is a worldwide thoroughbred leader with major stud operations in Ireland and the United States, had been particularly keen to secure Pierro for stud duties.

"Everyone has been watching Pierro after what he did as a two-year-old," Magnier said.

"He is one of the best two-year-olds we have seen in over 30 years and he trained on to win Group 1 races as a three-year-old.

"His race record is unbelievable and a lot of the reasons for that is because this horse was so well managed by Greg and Donna, and their trainer, Gai Waterhouse.

"Listen, Coolmore is lucky to be standing this horse - it is very exciting for all of us involved."

Tom Magnier and Greg KolivosSource:The Daily Telegraph

Magnier said a stud fee for Pierro is likely to be announced on Monday and Coolmore is expecting the sire will serve at least 150 broodmares in his debut season later this year. There is also every chance Pierro could stand in Ireland or the US in the northern hemisphere breeding season from next January, according to Magnier.

"This horse has fantastic appeal," Magnier said. "He is a great out-cross for Danehill mares. Everyone in Europe knows about Pierro - he would not be a hard horse to 'fill' wherever he stands.

"To have Pierro and So You Think standing at Coolmore is amazing as they are the two best Australian stallions prospects we have seen in a long, long time."

The feel-good story of how Kolivos came to own Pierro began a decade earlier when he used to go to the races just to watch champion Lonhro.

"I was a big Lonhro fan," Kolivos said.

Kolivos had raced a few horses with mixed success, including a share in The Metropolitan winner Herculian Prince but he really hit the jackpot at the Gold Coast Magic Millions Yearlings sales two years ago.

Donna reminded her husband how he had always wanted to own a horse by Lonhro. Kolivos then selected a Lonhro colt out of Miss Right Note sight unseen and paid $230,000 for the yearling.

"I picked him out on pedigree. He was by Lonhro out of a Daylami mare from a good European family. He was the most expensive Lonhro in the sale," he said.

Pierro was a champion from the moment he hit the racetrack. He won all six starts as a two-year-old, including the coveted Sydney triple crown of the Golden Slipper, ATC Sires Produce Stakes and Champagne Stakes.

He had another eight starts this season, winning five, including Group 1 successes against older horses in the Canterbury Stakes and George Ryder Stakes.

Pierro was placed in his three defeats - second in the Caulfield Guineas and third in the Cox Plate last spring, before his close second in the Doncaster Mile when attempting to carry a record weight for a three-year-old of 57kg.

His total earnings were more than $4.5 million from just 14 starts.

"We know how privileged we are to have owned and raced a horse as good as Pierro," Kolivos said.

"We pinch ourselves every single day. Donna and I got involved in racing because I've always loved being around horses and I love the sport. When we started racing some of our own, we had no great aspirations.

"We just wanted to have some fun and then Pierro lands in front of us.

"Over the last two years, look at the wild and fabulous journey he has taken us on. Gai Waterhouse did a marvellous job training and developing this colt and we could never have dreamt of this.

"For most people horses like Pierro don't come along in a lifetime in racing."